Flag Register - Epson RA8804 CE Applications Manual

RA8804 CE
3) USEL (Update Interrupt Select) bit
This bit is used to define if the RTC should output a "second update" or "minute update" interrupt, allowing to
synchronize external clocks with the time registers of the RTC.
USEL
Write/Read
4) TE (Timer Enable) bit
This bit controls the start/stop setting for the fixed-cycle timer interrupt function.
Writing a "1" to this bit specifies starting of the fixed-cycle timer interrupt function (a countdown starts from a preset
value).
Writing a "0" to this bit specifies stopping of the fixed-cycle timer interrupt function.
5) FSEL0, 1 (FOUT frequency Select 0, 1) bits
The combination of these two bits is used to set the FOUT frequency.
Note: All frequencies are temperature compensated!
FSEL0,1
Write/Read
6) TSEL0, 1 (Timer Select 0, 1) bits
The combination of these two bits is used to set the countdown period (source clock) for the fixed-cycle timer
interrupt function (four settings can be made).
TSEL0,1
Write/Read

8.2.6. Flag register

Address
0E
1. The default value is the value that is read (or is set internally) after powering up from 0 V.
"o" indicates write-protected bits. A zero is always read from these bits.
2.

This register is used to detect the occurrence of various interrupt events and low voltage which might
compromise the reliability of provided time and data.
1) UF (Update Flag) bit
If set to "0" beforehand, this flag bit's value changes from "0" to "1" when a time update interrupt event has
occurred. Once this flag bit's value is "1", its value is retained until a "0" is written to it.
For details, see 8.4. Time Update Interrupt Function.
2) TF (Timer Flag) bit
If set to "0" beforehand, this flag bit's value changes from "0" to "1" when a fixed-cycle timer interrupt event has
occurred. Once this flag bit's value is "1", its value is retained until a "0" is written to it.
For details, see 8.3. Fixed-cycle Timer Interrupt Function.
3) AF (Alarm Flag) bit
If set to "0" beforehand, this flag bit's value changes from "0" to "1" when an alarm interrupt event has occurred.
Once this flag bit's value is "1", its value is retained until a "0" is written to it.
For details, see "8.5. Alarm Interrupt Function".
Data
0 second update
1 minute update
FSEL1 FSEL0
(bit 3) (bit 2)
0
0
1
1
TSEL1 TSEL0
(bit 1) (bit 0)
0
0
1
1
Function bit 7
Flag register 
(Default) (0)
update interrupts
Default
FOUT frequency
0
32768HzOutput
1
1024HzOutput
0
1HzOutput
1
32768HzOutput
Source clock
0 4096 Hz
1 64 Hz
"Second update" / Once per second
0
"Minute update" / Once per minute
1
bit 6 bit 5 bit 4
 UF TF
(0) (0) (0)
Page - 11
Auto reset time
t
RTN
500 ms
Min. 7.813 ms
Default
/ Once per 244.14 s
/ Once per 15.625 ms
bit 3 bit 2 bit 1
AF  VLF
(0) (0) (1)
bit 0
VDET
(1)
ETM60E-02